if you have photoshop you can find a bunch of photoshop brushes on Deviantart that will give you that floral background and you can make them what ever color you want.

if you don’t have photoshop you can google wedding stock and you should find stock images you can use for free. just make sure it’s free other wise yeah.. nasty things can happy if an artist see’s their work that wasn’t asked to be used.

Edit: if you don’t find something you like i would be more then happy to make a background. i love working on photoshop and it would be fun.